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Dissertations / Theses on the topic 'Lipid degradation'
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Amir, Alipour Mohsen. "Effect of EPA on Intercellular Lipid Droplets Degradation." Thesis, Université d'Ottawa / University of Ottawa, 2017. http://hdl.handle.net/10393/36108.
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Although the beneficial effects of omega-3 fatty acid in reducing the risk of various of human diseases, such as hypertriglyceridemia and nonalcoholic fatty liver disease, have been demonstrated in clinical and pre-clinical studies, the mechanism of its action is poorly understood.
several studies has been reported that Dietary supplementation with fish oil induces many changes in plasma TG profile.
N-3 fatty acid found in fish oil has been reported that reduce plasma TG and VLDL lev- els. Intercellular lipid droplets is the key regulator of plasma fatty acids and lipoproteins level.
Here we show that n-3 fatty acid supplementation triggers intercellular lipid droplets degradation independent from known fatty acid mobilization pathways namely lipophagy and lipolysis .
ATGL and HSL are consider as two major lipolysis enzymes.SiRNA study of these two lipolysis enzymes did not attenuate lipid droplets degradation.
Lipophagy has been reported as a selective mechanism for degradation of lipid droplets during the starvation condition. Knock down of autophagy (macroautophagy) related pro- teins, could not block degradation of intercellular lipids by EPA.
Degradation of lipid droplets is lysosomes dependent and requires lysosomal motility machinery. Lysosomes are interacting directly with lipid droplets during the process that is similar to kiss and run pattern.
The morphological examination of this process by electron microscopy indicated its re- semblance to microautophagy like structure.
Importantly, (over expression) Arl8b which has been shown that play a role in peripheral distribution of lysosomes along with FYCO1, specifically accelerates the effect of EPA on degradation of intercellular lipid droplets independent from its role in engagement of lysosomal plus end distribution.
in particular, Arl8b recruited HOPS protein complex in EPA dependent fashion and si- lencing of HOPS complex interfered with normal lysosomal degradation of lipid droplets. Thus, this finding reveals new mechanism for intercellular lipid mobilization and offer an explanation for the therapeutic benefits of omega-3 fatty acids.
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Asano, Lisa. "Vitamin D metabolite, 25-Hydroxyvitamin D, regulates lipid metabolism by inducing degradation of SREBP/SCAP." 京都大学 (Kyoto University), 2017. http://hdl.handle.net/2433/225512.
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Lee, Yoon-Hee. "Effect of Riboflavin and Lumichrome Degradation on the Oxidative Stability of Salad Dressing." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1253631242.
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Tipsrisukond, Narin. "Impact of lipid degradation processes, and supercritical carbon dioxide extraction on flavor characteristics of lard /." free to MU campus, to others for purchase, 2003. http://wwwlib.umi.com/cr/mo/fullcit?p3091972.
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Carbone, David L. "Effects of the lipid peroxidation product 4-hydroxy-2-nonenal on protein degradation and refolding pathways /." Connect to full text via ProQuest. IP filtered, 2005.
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Sato, Shin. "Degradation of cis-1,4-polyisoprene rubbers by white rot fungi and manganese peroxidase-catalyzed lipid peroxidation." Kyoto University, 2005. http://hdl.handle.net/2433/78163.
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Kyoto University (京都大学)<br>0048<br>新制・課程博士<br>博士(農学)<br>甲第11635号<br>農博第1491号<br>新制||農||908(附属図書館)<br>学位論文||H17||N4028(農学部図書室)<br>UT51-2005-D384<br>京都大学大学院農学研究科応用生命科学専攻<br>(主査)教授 渡邊 隆司, 教授 島田 幹夫, 教授 東 順一<br>学位規則第4条第1項該当
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Zahoor, Muhammad kashif. "Genome wide analysis for novel regulators of growth and lipid metabolism in drosophila melanogaster." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00664844.
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The evolutionary conserved insulin and nutrient signaling network regulates growth andmetabolism. Nutrients are directly utilized for growth or stored, mostly as triglycerides. InDrosophila, activation of insulin/nutrient signaling in the fat body (the fly equivalent of liverand adipose tissue), causes an increase in fat stores composed of several small-size lipiddroplets (LDs). Conversely, fasting produces an increase in LD size and a decrease in fatcontents. The TOR kinase and its substrate S6 kinase (S6K) play a central role in this response,and particularly in Drosophila, they have been shown to orchestrate cell-autonomous andhormone-controlled growth. However, despite extensive research studies on different modelorganisms (mouse, fly, worm) to decipher the molecular and physiological functions of S6K,nothing is known about how its degradation is regulated.Taking advantage of the inducible RNA interfering (RNAi) library from NIG (Japan), we haveperformed three genetic screens to identify novel regulators of steroidogenesis, lipidmetabolism and dS6K-dependent growth. First, RNAi lines were screened in the ring gland; anorgan that controls the progression of the developmental steps by producing the steroidhormone ecdysone. Out of 7,000 genes screened, 620 positive candidates were identified toproduce developmental arrest and/or overgrowth phenotypes. Then, we challenged 4,000 genesby RNAi screening able to recapitulate the larger sized LD phenotype as obtained uponstarvation, leading to the identification of 24 potential candidates. Finally, the RNAi lines werescreened for their ability to enhance a growth phenotype dependent of the Drosophila S6K(dS6K). Out of 7,000 genes screened, 45 genes were identified as potential negative regulatorsof dS6K. These genes were further used to design a novel protein-protein interaction networkcentered on dS6K through the available data from yeast-2-hybrid (Y2H) assay. The most potentinteractors were then analyzed by treatment of cultured S2 cells with the corresponding doublestrand RNA (dRNA). Western blotting thus, allowed us to discriminate between the geneproducts that regulate dS6K levels versus those that regulate its phosphorylation, as a hallmarkfor its kinase activity. Interestingly, archipelago (ago), which encodes a component of an SCFubiquitinligase known to regulate the degradation of dMyc, Cyclin E and Notch, was identifiedas a negative regulator of dS6K-dependent growth. Based on the Y2H available data showingthat Ago and dS6K interact each other and the presence of a putative Ago-interaction motif indS6K, we hypothesized that Ago causes an ubiquitin-mediated degradation of dS6K. Ourmolecular data showed that loss of ago caused an elevated level of dS6K, which confirms arole of Ago in controlling dS6K degradation. Altogether our findings emphasize the importanceof the saturating screening strategies in Drosophila to identify novel regulators of metabolicand signaling pathways.
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Ruggiano, Annamaria 1985. "Control of endoplasmatic reticulum homeostasis by Doa10-dependent protein degradation." Doctoral thesis, Universitat Pompeu Fabra, 2015. http://hdl.handle.net/10803/384851.
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La función, forma e identidad de los orgánulos celulares es determinada, en gran medida, por su composición lipídica y proteica. Para mantener el equilibrio celular, las tasas de síntesis y degradación tanto de proteínas como de lípidos deben controlarse con exactitud. La proteólisis mediante el sistema ubiquitino-proteosómico cumple un papel importante en la regulación del tiempo de vida media de una variedad de proteínas. El normal funcionamiento de numerosos procesos celulares requiere degradación selectiva de proteínas en forma precisa y oportuna; entre estos procesos algunos ejemplos prominentes son: tráfico intracelular y secreción, eliminación de polipéptidos dañados y reparación de ADN. Valga resaltar que anomalías en el sistema ubiquitino-proteosómico han sido asociadas a varias patologías humanas.
Durante la proteosíntesis algunas proteínas mal plegadas se generan, de forma constitutiva, en la membrana y en el lumen del retículo endoplasmático (RE). Estas especies, potencialmente tóxicas, son eliminadas mediante el sistema ubiquitino-proteosómico por una ruta de control de calidad denominada degradación asociada al retículo endoplasmático (DARE). Más allá de esta bien conocida y estudiada función, DARE controla también la abundancia de algunas proteínas del RE correctamente plegadas y funcionales, pero de vida media corta. En este caso la selección y degradación de substratos responde a condiciones fisiológicas específicas y constituye un proceso regulado. De particular relevancia, la síntesis de esteroles se ajusta a los requerimientos celulares a través del control de la estabilidad de la enzima HMGR mediante un mecanismo de retroalimentación.
A pesar de su importancia en la homeostasis del RE, hasta el momento sólo se conocen algunos pocos ejemplos de degradación regulada mediada por DARE.
En el RE de S.cerevisiae tres enzimas ligasas de ubiquitina, entre ellas Doa10, participan en la degradación de proteínas mal plegadas. Con el propósito de encontrar sustratos regulados de Doa10 llevamos a cabo un examen proteómico. Encontramos varios candidatos, involucrados en diversas funciones celulares, y caracterizamos algunos de ellos en mayor profundidad. Demostramos que la degradación dependiente de Doa10 tiene un impacto crucial en la homeostasis de lípidos por medio de la eliminación regulada de Erg1, una enzima del anabolismo de esteroles. Más aún, encontramos que Doa10 lleva a la degradación de proteínas pertenecientes a los cuerpos lipídicos, un orgánulo derivado del RE; este descubrimiento resalta el rol que DARE juega en el control espacial de proteínas y el mantenimiento de la identidad del RE.<br>The function, shape and identity of cellular organelles are too a large extent determined by their lipid and protein composition. In order to maintain cellular homeostasis, the rate of synthesis and degradation of proteins and lipids must be accurately controlled. Proteolysis by the ubiquitin-proteasome system plays a major role in regulating the half-lives of a range of proteins. A multitude of cellular processes depends on timely controlled and selective protein degradation; just to mention a few, these include intracellular trafficking and secretion, elimination of damaged polypeptides and DNA repair. Remarkably, anomalies in the ubiquitin-proteasome system have been linked to several human pathologies.
Misfolded proteins in the membrane and lumen of the endoplasmic reticulum (ER) are constitutively generated during protein biosynthesis. These species are potentially toxic and are eliminated by the ubiquitin-proteasome system through a quality control pathway called ER-associated protein degradation (ERAD). Beyond this well-studied role, ERAD controls the levels of some folded, functional but short-lived ER proteins by eliminating them under a specific physiological condition, thereby in a regulated fashion. Of note, sterol production is adjusted to cell needs through feedback control of the HMGR enzyme stability.
Despite its importance in ER homeostasis, regulated degradation through ERAD still accounts for only few examples.
Yeast Doa10 is one of three ER ubiquitin ligase enzymes implicated in the degradation of misfolded proteins. To seek for regulated Doa10 clients, we pursued a proteomics screening. We identified potential targets involved in diverse cellular functions and further characterized some of them. We demonstrate that Doa10-dependent degradation critically impacts lipid homeostasis through regulated disposal of the sterol pathway enzyme Erg1. Moreover, we show that Doa10 mediates degradation of proteins belonging to lipid droplets, an ER-derived organelle; this finding highlights a role for ERAD in protein spatial control and maintenance of ER identity.
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Schwab, Martin. "Degradation of lipid based drug delivery systems and characterization of semi-synthetic spider silk proteins for the application in pharmaceutical technology." Diss., Ludwig-Maximilians-Universität München, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-165238.
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Maheshwari, Neeraj. "Biofuntionalisation of PLGA based polymer nanoparticles for vectorization : interaction with biomimetic lipid membranes and bio-controlled release." Thesis, Compiègne, 2017. http://www.theses.fr/2017COMP2357.
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Cette thèse vise à développer des nanoparticules de PLGA pour la vectorisation et à étudier l’interaction de ces nanoparticules avec des bicouches phospholipidiques imitant les membranes cellulaires. Pour la vectorisation passive, les changements physico-chimiques ont été contrôlés en incubant les NPs de PLGA (50:50) dans différentes conditions de pH tamponné à des intervalles de temps accrus. Le PLGA a montré plusieurs comportements de dégradation différant selon le pH. La formation de pores a été observée à pH élevé (conditions basiques) tout en préservant le volume des particules mais en modifiant la densité. Par opposition, à faible pH, une érosion superficielle des particules conduisant à une diminution de leur taille a été démontrée. Cette étude a été réalisée à l'aide de la DLS, l’ESEM et la spectrophotométrie. Pour la vectorisation active, les parois des capsules de PLGA (75:25) ont été modifiées par addition de phospholipides. La libération de la sonde fluorescente hydrophile, la calcéine, a été contrôlée en augmentant la température. On a observé qu'avec le DOPC (0,31 mM), la vectorisation peut être déclenchée à l'aide de détergents ou d'une enzyme (PLA2). Dans le cadre de cette étude, nous avons proposé la formation d'un complexe lipide-polymère ayant lieu à l'intérieur de la matrice, ce qui le rend vulnérable aux enzymes ou détergents induisant sa libération. L'effet des NPs de PLGA sur les bicouches phospholipidiques imitant la membrane cellulaire a été réalisé à l'aide de sondes fluorescentes moléculaires (Prodan et Laurdan). L'étude a été effectuée en calculant la polarisation généralisée (GP) sous l'influence des NPs de PLGA (50:50 et 75:25). L'interaction ayant lieu s’avérait être un phénomène de surface et aucune effet des NPs sur la perméabilité des membranes modèles LUVs et SUVs n’a été souligné. La valeur de Tm des phospholipides est également maintenue lorsque l’étude est menée avec le Laurdan. Les études de GP mené avec la sonde Prodan fournissent la première méthode originale pour déterminer la Tg de PLGA dans des conditions aqueuses. C'est une méthode rapide et facile qui détermine la valeur de Tg de PLGA en temps réel et en utilisant une très petite quantité de l'échantillon. Cette interaction n'est pas affectée par la composition des membranes cellulaires imitant les bicouches<br>This thesis aims at developing PLGA nanoparticles for controlled release and investigating its interaction with phospholipid bilayers mimicking cell membranes. For passive controlled release the physiochemical changes were monitored by incubating the PLGA (50:50) NPs in different buffered pH conditions at increased time intervals. PLGA exhibited dissimilar degradation behavior with pore formation for high pH (basic conditions) maintaining the volume of the particles but change in the density, while at low pH it showed surface erosion. There is decrease in the particle size upon incubating in low pH. This study was carried out using DLS, ESEM and spectrophotometry. For active release the walls of PLGA (75:25) capsules were modulated using phospholipids. The release of hydrophilic fluorescent probe Calcein was monitored with increasing the temperature. It was observed that with DOPC (0.31mM) the release can be triggered using detergents or an enzyme (PLA2). We propose the formation of a lipid-polymer complex within the polymer matrix forming plugs which are vulnerable to enzymes/detergents inducing release. The effect of PLGA NPs over the phospholipid bilayers mimicking cell membrane was carried out using molecular fluorescent probes (Prodan and Laurdan). The study was carried out by calculating the generalised polarisation (GP) under the influence of PLGA NPs (50:50 and 75:25). It is found that the interaction is a surface phenomenon and there is no influence of NPs over the permeability of model membranes LUVs and SUVs. The Tm value of the phospholipids is also maintained when studied with Laurdan. Prodan probe GP studies provide first original method to determine the Tg of PLGA in complete aqueous conditions. It is a rapid and easy method which determines the Tg value of PLGA in real time using very small quantity of the sample. This interaction is not affected by the composition of the bilayer mimicking cell membranes
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Schwab, Martin [Verfasser], and Gerhard [Akademischer Betreuer] Winter. "Degradation of lipid based drug delivery systems and characterization of semi-synthetic spider silk proteins for the application in pharmaceutical technology / Martin Schwab. Betreuer: Gerhard Winter." München : Universitätsbibliothek der Ludwig-Maximilians-Universität, 2014. http://d-nb.info/1046785257/34.
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Masarin, Fernando. "Estudo da degradação de lignina iniciada por metabólicos extracelulares extraídos de cultivos de Ceriporiopsis subvermispora." Universidade de São Paulo, 2010. http://www.teses.usp.br/teses/disponiveis/97/97131/tde-27092012-111546/.
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Ceriporiopsis subvermispora é um fungo filamentoso, muito seletivo na degradação de lignina e, por isso, tem sido uma das espécies mais estudadas no processo de biopolpação. A biopolpação consiste em um tratamento biológico da madeira que antecede etapas convencionais de polpação, proporcionando níveis de economia de energia elétrica no processo que podem atingir valores de 30 a 40%. Para degradar a lignina, esse fungo secreta a enzima manganês-peroxidase (MnP), a qual requer um ácido carboxílico para quelar e transportar íons Mn3+ oriundos do seu ciclo catalítico. O complexo quelante-Mn3+ degrada apenas frações fenólicas da lignina, porém pode também iniciar a peroxidação de lipídeos e com isso gerar radicais peroxila que apresentam capacidade oxidativa suficiente para degradar estruturas não-fenólicas da lignina. Com base nesses aspectos, o presente trabalho teve o objetivo de avaliar a degradação de lignina por reações que envolvem a peroxidação de ácido linoléico iniciadas por metabólitos extracelulares extraídos de cultivos de C. subvermispora. Também foram avaliados sistemas miméticos baseados nos íons Fe2+ e Mn3+ como iniciadores das mesmas reações. Essencialmente, foi estudada a degradação de lignina in vitro em reações iniciadas por sistemas compostos que incluíram, MnP/Mn+2/H2O2, Fe3+/agentes redutores de Fe3+ produzidos durante a biodegradação da madeira, íons Mn+3 ou íons Fe+2, todos adicionados ao ácido linoléico. Para realizar esse estudo foi necessário preparar, tanto MnP, quanto compostos redutores de Fe3+, em cultivos de C. subvermispora. Também foram preparados e caracterizados dois substratos para as reações em estudo. Esses substratos compreenderam um complexo lignina-carboidrato (CLC) e um modelo de um material lignocelulósico completo, porém moído e livrado de toda a fração de extrativos. Nos dois casos, o material de partida foi à madeira de Eucalyptus grandis. A caracterização química desses substratos indicou um teor de lignina de 44,8% e 29,0%, respectivamente. Reações de peroxidação de ácido linoléico iniciadas pelos sistemas em estudo mostraram que todos foram efetivos para esse propósito, sendo que as maiores taxas de consumo de oxigênio durante essas reações foram observadas nos meios reacionais que continham Fe2+ em solução. O CLC inibiu as reações de peroxidação quando adicionado ao meio reacional em concentraçãoes maiores do que 0,3 mg/mL. Entretanto, reações prolongadas por 72 h com o CLC numa concentração inicial de 1 mg/mL indicaram que ele sofreu despolimerização. As vias de degradação da lignina contida no CLC ou na madeira de E. grandis moída envolveram a despolimerização da molécula, ou simplesmente a oxidação das cadeias laterais e das estruturas fenólicas livres. Quando o sistema foi baseado na ação de MnP/Mn+2/H2O2/ácido linoléico, foram comprovadas vias de degradação da lignina que envolveram desde a simples oxidação do carbono-α até a quebra de ligações do tipo β-O-4 e/ou entre os carbonos α e β. Os resultados obtidos corroboraram dados anteriormente publicados para a ação de C. subvermispora in vivo. Uma exceção foi à observação da reação de simples oxidação do Cα nos sistemas in vitro, que havia sido descartada em trabalhos anteriores que se basearam na caracterização de lignina contida em madeira biotratada por C. subvermispora (sistema in vivo). Os resultados permitiram concluir que vários sistemas miméticos podem iniciar a peroxidação de ácido linoléico in vitro. Quando essas reações foram conduzidas na presença de lignina (CLC ou E. grandis moído) foi possível observar transformações importantes na estrutura da lignina que eventualmente poderiam ser exploradas, por exemplo, em etapas de processos de branqueamento de polpas kraft.<br>The white-rot fungus Ceriporiopsis subvermispora degrades lignin selectively, being one of the most studied species in biopulping. Biopulping consists of a biological treatment of wood that precedes conventional pulping stages. The process can provide up to 30-40% of energy savings in mechanical pulping. To degrade lignin, this fungus secretes the enzyme manganese-peroxidase (MnP), which needs carboxylic acids to chelate and transport Mn3+ ions formed in the catalytic cycle of the enzyme. The chelate-Mn3+ complex is able to degrade phenolic structures of lignin; however, can also initiate lipid peroxidation reactions generating peroxyl radicals that are able to degrade nonphenolic lignin structures. Based on this background, the aim of this work was to evaluate lignin degradation through linoleic acid peroxidation reactions initiated by extracellular metabolites recovered from C. subvermispora cultures. Some biomimetic systems based on Fe2+ and Mn3+ ions were also evaluated as initiators of such reactions. The lignin degradation was studied in reaction systems composed of MnP/Mn+2/H2O2, Fe3+-reducing compounds produced during wood biodegradation by C. subvermispora, Mn+3 or Fe+2 ions, all of them in the presence of linoleic acid. To perform this study, MnP and Fe3+-reducing compounds were initially produced in C. subvermispora cultures. Two different reaction substrates were also prepared. One was a lignin-carbohydrate complex (LCC) and, the other, was a complete lignocellulosic material that was milled and extracted to remove the extractive fraction. Both substrates were prepared from Eucalyptus grandis wood. The chemical characterization of the substrates showed 44.8 % and 29.0 % of total lignin, respectively. Linoleic acid peroxidation reactions initiated by the studied systems showed that all of them were efficient on this purpose. The highest oxygen consumption rates during these reactions were observed in the Fe2+ initiated reactions. The LCC inhibited the peroxidation reactions when added to the reaction medium at concentrations higher than 0.3 mg/mL. However, prolonging the reactions up to 72h with LCC at 1 mg/mL showed that it was depolymerized. The lignin degradation routes involved depolymerization or simple side chain and free-phenolic structure oxidations. When the reactive system was based on the use of MnP/Mn+2/H2O2/linoleic acid, some lignin degradation routes were demonstrated and they included Cα-oxidation, as well as β-O-4 and/or Cα-Cβ cleavages. These results corroborate previous findings published for the action of C. subvermispora in vivo. One exception was the simple Cα oxidation that was observed for the in vitro reactions, but was ruled out by previous works that were based on the characterization of residual lignins extracted from wood samples biotreated by C. subvermispora (in vivo system). The current results permitted to conclude that several mimetic systems were able to initiate linoleic acid peroxidation in vitro. When these reactions were performed in the presence of lignin (LCC or milled E. grandis) it was possible to show the occurrence of several lignin transformation reactions that could be exploited, for example, in pulp bleaching processes.
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Hult, Louise. "Fäst vid keramik : En experimentell undersökning av lipidrester i keramik, med GC-MS-metod, efter nedbrytningsförsök." Thesis, Stockholms universitet, Arkeologiska forskningslaboratoriet, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-87173.
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Thisis an experimental study of lipid residues within the field of laboratoryarcheology. Pottery was made in a time like manner and used to cook grain and Icelandmoss and exposed to an organized biodegradation experiment inside an incubatorfor later analyzes with the GC-MS-method. Tests were also taken from pottery,grain and Iceland moss that had not been exposed for a biodegrading attempt.The grain is a domesticated cereal and the Icelandic moss fungi-alga mix. Thetest results showed mostly saturated fatty acids, sterols and monoacylglycerolsof saturated fatty acids. Within the laboratory archeology, ergosterol has beensuggested as a possible biomarker for yeast and alcohol fermentation. TheIceland moss contains ergosterol and is therefore relevant for the study whenit can be compared to archeological pottery that contains ergosterol. Theresults didn’t show any traces of ergostrol with the biodegraded pottery, butlow traces of cholesterol witch probably is contaminations from the handlingwith the pottery.
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Jin, Qi. "Effects of Rosemary Extract and Propyl Gallate as Antioxidative Oil Additives and Whey Protein Isolate as an Oil Barrier on Degradation of Oil and Production of Fried Chicken." Ohio University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1523653298103237.
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Bachratá, Radka. "Molecular study of lipids in humic acids by sequential chemical degradation." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2009. http://www.nusl.cz/ntk/nusl-216468.
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Lipidy v půdě vykazují poměrně vysokou resistenci k biodegradaci, mohou proto tak zajistit informace o zdrojích organické hmoty a diagenetických procesech. Půdní organická hmota je vysoce heterogenní a vyskytují se v ní různé dynamické systémy. Vztahy mezi těmito systémy a molekulární strukturou ještě nejsou úplně známy. Analýza lipidů a bitumenu byla provedena u dvou vzroků (rašelina a lignit). Množství skupin sloučenin (volné uhlovodíky a volné ketony, vázané alkoholy, vázané mastné kyseliny, vázané -hydroxy kyseliny, volné dikyseliny a polycyklické sloučeniny) bylo idetifikováno pro oba vzorky a jejich distribuce byly určeny. GC/MS analýza volných a vázaných lipidů zjistila jejich různé zdroje během chemické degradace. Některé podobné znaky mohou být znakem uchovávání části vosků a suberinu z vyšších rostlin (dlouhé řetězce vázaných mastných kyselin). Velké rozdíly v molekulárním složení lipidů byly pozorovány mezi vzorky, dokládající význam studia lipidů z mladého sedimentu (rašelina) a starého (lignit).
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Vlčková, Bohumila. "Testování komerčních přípravků do odlučovačů tuků." Master's thesis, Vysoké učení technické v Brně. Fakulta chemická, 2008. http://www.nusl.cz/ntk/nusl-216440.
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Diploma thesis was aimed at testing of five commercial products for separators of lipids. Performed study should to shown that in produts are presented lipase-produducing microoganisms, event. that in products are also lipolytics enzymes as addition. The products was cultivated by solid-state and submerged fermentations and subsequently was tested their properties as is lipolytic activity, the amount of free fatty acids etc. Solid-state fermentation used Tributyrin Agar Base where Tributyrin was used as a substrate. Submerged fermentation used special prepared medium where was olive oil. Methods using in this study served for detection and qualification of lipase-produducing microoganisms in individual products. For detection of lipase-produducing bacterial spieces was used Spirit Blue Agar. In this case was used Tributyrin and Tween 80 as a substrate. Lipolytic activity was measured by spectrophotometry and degradation of lipids was measured titrimetry. Performed study demonstrated that all tested products have ability to degradation of lipids.
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au, y. kuang@exchange curtin edu, and Yunhua Kuang. "Enhancing Anaerobic Degradation of Lipids in Wastewater by Addition of Co-substrate." Murdoch University, 2002. http://wwwlib.murdoch.edu.au/adt/browse/view/adt-MU20040820.132229.
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Anaerobic treatment systems are becoming increasingly popular to treat complex organic wastes that contain carbohydrates, proteins and lipids. Lipids are widely found in sewage and industrial wastewaters. Dairy, edible oil, fat refining, slaughterhouse, wool scouring, meat processing plants and grease-trap wastes from restaurants generate wastewater high in lipids. Although it is well known that lipids can be degraded by biological process, they have been reported to inhibit anaerobic processes by causing sludge flotation and wash-out. The inhibitory effect of lipids in anaerobic process has also been attributed to the long-chain fatty acids (LCFAs) which are the hydrolysed products of lipids. It has been shown that LCFA and lipids inhibit the formation of granular sludge in Upflow Anaerobic Sludge Blanket (UASB) reactors and that the adsorption of LCFAs on to the granules can result in its flotation and washout. It was also found that the degradation of LCFA was very poor.
Various techniques have been employed to enhance degradation of lipids and these include physico-chemical pre-treatment, application of two stage treatment employing new reactor designs like Expanded Granular Sludge Bed (EGSB). This thesis investigated the influence of co-substrates, both in the form of hydrolysed products and polymeric form, on reducing the toxicity and enhancing the degradation of LCFA and lipids in a single stage and two stage upflow anaerobic sludge blanket (UASB) reactors. The investigations were carried out on both microbiological and physico-chemical aspects. A combination of techniques including the use of light microscopy (LM), confocal laser scanning microscopy (CLSM), transmission electron microscopy (SEM) and Fluorescent In Situ Hybridisation (FISH) was used to study the characteristics of microbial aggregates and to locate microbial populations within these aggregates. The microbial populations visualised using FISH techniques were Bacteria, Archaea, Methanobacteriaceae, Methanomicrobiales and Methanosarcinaceae. The performance of digesters was also monitored by measuring bulk parameters such as concentration of residual substrates, intermediate products (LCFAs, volatile fatty acids), methane (or gas) production rate and chemical oxygen demand of treated effluent.
Initially batch assays were carried out to determine the effects of glucose (hydrolysis product of carbohydrate) and cysteine (hydrolysis product of protein) on the toxicity of sodium oleate (hydrolysis product of lipid) to methanogenesis. The results showed that glucose and cysteine addition could reduce the toxicity of sodium oleate on the methanogenesis and enhance the degradation of sodium oleate. While the addition of glucose had a better effect than cysteine on decreasing the toxicity of sodium oleate, the combination of glucose and cysteine had the optimal result to stimulate the degradation of sodium oleate.
Secondly the effect of addition of glucose, cysteine and sodium oleate as co-substrates on the characteristics of granules in an LCFA fed single stage UASB were investigated. It was shown that the addition of glucose produced the best results on the formation of granules while both cysteine and sodium oleate adversely affected the granule formation. In a LCFA inhibited digester glucose and cysteine addition enhanced the recoveries of different anaerobic microbial communities. Although the effects of glucose and cysteine on the various microbial groups were different, the combination of glucose and cysteine had the optimal results on recoveries of all bacterial groups.
The next half of the thesis investigated the influence of starch and yeast extract on the hydrolysis and degradation of canola oil by application of one and two stage UASB reactors. The results showed that the combined addition of protein and carbohydrate had an optimal effect on enhancing the hydrolysis of lipid compared to the addition of only protein or carbohydrate by promoting a balanced growth of the microbial groups. It was also demonstrated that a two- stage UASB reactor performed better in terms of extent of lipid hydrolysis and methanogenesis than a one-stage UASB reactor.
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Dobrzanski, Tatiane. "Sistema de respostas de Bacillus sp. à toxicidade induzida pelo herbicida Callisto e princípio ativo." UNIVERSIDADE ESTADUAL DE PONTA GROSSA, 2015. http://tede2.uepg.br/jspui/handle/prefix/941.
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Previous issue date: 2015-02-25<br>Excessive use of herbicides for weed control in agriculture causes a selective pressure on soil microbiota and waters near application area, changing environmental balance. Some microorganisms have developed metabolic pathways for degradation of these xenobiotics, although tolerance and degradation processes can generate free radicals and affect survival. This study aimed to analyze the system of responses from soil and water strains, submitted to selective pressure by the herbicide Callisto®. Strains CCT7729 and CCT7730, isolated from soil and water, respectively, were identified as Bacillus sp., and showed different degradation routes, with different metabolites, already described in the literature. Mesotrione and its metabolites, and especially its commercial product Callisto, affected cell viability and altered cell membrane lipids from the tested strains, however, Bacillus sp. CCT7729 presented a more efficient system of responses to oxidative stress. This strain exhibited a greater efficiency to degrade mesotrione, lower rates of peroxide, lower rates of MDA, SOD high activity and low activity of catalase, when compared to Bacillus sp. CCT7730. Changes in membrane lipids can be considered as a defense against oxidative stress strategy. These results indicated the existence from a variety of metabolic pathways for mesotrione degradation to Bacillus sp. Probably metabolites induce different levels of toxicity in bacteria, and Bacillus sp. CCT7730 possibly degraded mesotrione in even harmful compounds, unlike the water line. It is possible that these different responses are related to the home environments of each strain, suggesting plasticity responses of Bacillus sp. for adaptation to toxic substances in different environmental contexts.<br>O uso intenso de herbicidas para controle de ervas daninhas na agricultura provoca uma pressão seletiva na microbiota do solo e de águas próximas à área de aplicação, alterando o equilíbrio ambiental. Alguns microrganismos apresentam vias metabólicas de degradação desses xenobióticos, entretanto, a tolerância e os processos de degradação podem gerar radicais livres capazes de afetar a sobrevivência. Este trabalho teve como objetivo analisar o sistema de respostas de linhagens provenientes de solo e água, e que foram submetidas a pressão seletiva pelo herbicida Callisto. Uma linhagem isolada de cada um destes ambientes, identificadas respectivamente, como Bacillus sp. CCT7729 e Bacillus sp. CCT7730, apresentaram rotas de degradação diferenciadas, com metabólitos diferentes dos já descritos na literatura. O mesotrione, seus metabólitos, e principalmente o Callisto, afetaram a viabilidade celular das linhagens deste estudo e alteraram os lipídios de membrana celular, no entanto, Bacillus sp. CCT7729 apresentou um sistema de respostas ao estresse oxidativo mais eficiente. Esta linhagem exibiu uma maior eficiência em degradar o mesotrione, menores taxas de peróxido, menores taxas de MDA, atividade SOD elevada e uma baixa atividade da catalase, ao contrário de Bacillus sp. CCT7730. Modificações nos lipídios de membrana podem ser consideradas como uma estratégia de defesa contra estresse oxidativo. Os resultados também indicaram uma diversidade de vias metabólicas nas duas linhagens de Bacillus sp. para a degradação do mesotrione. Provavelmente os metabólitos induziram diferentes níveis de toxicidade nas bactérias, sendo que Bacillus sp. CCT7730 possivelmente degradou o mesotrione em compostos ainda nocivos, ao contrário da linhagem de água. É possível que essas diferentes respostas estejam relacionadas com os ambientes de origem de cada linhagem, sugerindo uma plasticidade de respostas apresentadas por linhagens Bacillus sp. para adaptação a substâncias tóxicas em diferentes contextos ambientais.
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Kuang, Yunhua. "Enhancing anaerobic degradation of lipids in wastewater by addition of co-substrate." Thesis, Kuang, Yunhua (2002) Enhancing anaerobic degradation of lipids in wastewater by addition of co-substrate. PhD thesis, Murdoch University, 2002. https://researchrepository.murdoch.edu.au/id/eprint/136/.
Full textAbstract:
Anaerobic treatment systems are becoming increasingly popular to treat complex organic wastes that contain carbohydrates, proteins and lipids. Lipids are widely found in sewage and industrial wastewaters. Dairy, edible oil, fat refining, slaughterhouse, wool scouring, meat processing plants and grease-trap wastes from restaurants generate wastewater high in lipids. Although it is well known that lipids can be degraded by biological process, they have been reported to inhibit anaerobic processes by causing sludge flotation and wash-out. The inhibitory effect of lipids in anaerobic process has also been attributed to the long-chain fatty acids (LCFAs) which are the hydrolysed products of lipids. It has been shown that LCFA and lipids inhibit the formation of granular sludge in Upflow Anaerobic Sludge Blanket (UASB) reactors and that the adsorption of LCFAs on to the granules can result in its flotation and washout. It was also found that the degradation of LCFA was very poor.
Various techniques have been employed to enhance degradation of lipids and these include physico-chemical pre-treatment, application of two stage treatment employing new reactor designs like Expanded Granular Sludge Bed (EGSB). This thesis investigated the influence of co-substrates, both in the form of hydrolysed products and polymeric form, on reducing the toxicity and enhancing the degradation of LCFA and lipids in a single stage and two stage upflow anaerobic sludge blanket (UASB) reactors. The investigations were carried out on both microbiological and physico-chemical aspects. A combination of techniques including the use of light microscopy (LM), confocal laser scanning microscopy (CLSM), transmission electron microscopy (SEM) and Fluorescent In Situ Hybridisation (FISH) was used to study the characteristics of microbial aggregates and to locate microbial populations within these aggregates. The microbial populations visualised using FISH techniques were Bacteria, Archaea, Methanobacteriaceae, Methanomicrobiales and Methanosarcinaceae. The performance of digesters was also monitored by measuring bulk parameters such as concentration of residual substrates, intermediate products (LCFAs, volatile fatty acids), methane (or gas) production rate and chemical oxygen demand of treated effluent.
Initially batch assays were carried out to determine the effects of glucose (hydrolysis product of carbohydrate) and cysteine (hydrolysis product of protein) on the toxicity of sodium oleate (hydrolysis product of lipid) to methanogenesis. The results showed that glucose and cysteine addition could reduce the toxicity of sodium oleate on the methanogenesis and enhance the degradation of sodium oleate. While the addition of glucose had a better effect than cysteine on decreasing the toxicity of sodium oleate, the combination of glucose and cysteine had the optimal result to stimulate the degradation of sodium oleate.
Secondly the effect of addition of glucose, cysteine and sodium oleate as co-substrates on the characteristics of granules in an LCFA fed single stage UASB were investigated. It was shown that the addition of glucose produced the best results on the formation of granules while both cysteine and sodium oleate adversely affected the granule formation. In a LCFA inhibited digester glucose and cysteine addition enhanced the recoveries of different anaerobic microbial communities. Although the effects of glucose and cysteine on the various microbial groups were different, the combination of glucose and cysteine had the optimal results on recoveries of all bacterial groups.
The next half of the thesis investigated the influence of starch and yeast extract on the hydrolysis and degradation of canola oil by application of one and two stage UASB reactors. The results showed that the combined addition of protein and carbohydrate had an optimal effect on enhancing the hydrolysis of lipid compared to the addition of only protein or carbohydrate by promoting a balanced growth of the microbial groups. It was also demonstrated that a two- stage UASB reactor performed better in terms of extent of lipid hydrolysis and methanogenesis than a one-stage UASB reactor.
20
Kuang, Yunhua. "Enhancing anaerobic degradation of lipids in wastewater by addition of co-substrate." Kuang, Yunhua (2002) Enhancing anaerobic degradation of lipids in wastewater by addition of co-substrate. PhD thesis, Murdoch University, 2002. http://researchrepository.murdoch.edu.au/136/.
Full textAbstract:
Anaerobic treatment systems are becoming increasingly popular to treat complex organic wastes that contain carbohydrates, proteins and lipids. Lipids are widely found in sewage and industrial wastewaters. Dairy, edible oil, fat refining, slaughterhouse, wool scouring, meat processing plants and grease-trap wastes from restaurants generate wastewater high in lipids. Although it is well known that lipids can be degraded by biological process, they have been reported to inhibit anaerobic processes by causing sludge flotation and wash-out. The inhibitory effect of lipids in anaerobic process has also been attributed to the long-chain fatty acids (LCFAs) which are the hydrolysed products of lipids. It has been shown that LCFA and lipids inhibit the formation of granular sludge in Upflow Anaerobic Sludge Blanket (UASB) reactors and that the adsorption of LCFAs on to the granules can result in its flotation and washout. It was also found that the degradation of LCFA was very poor.
Various techniques have been employed to enhance degradation of lipids and these include physico-chemical pre-treatment, application of two stage treatment employing new reactor designs like Expanded Granular Sludge Bed (EGSB). This thesis investigated the influence of co-substrates, both in the form of hydrolysed products and polymeric form, on reducing the toxicity and enhancing the degradation of LCFA and lipids in a single stage and two stage upflow anaerobic sludge blanket (UASB) reactors. The investigations were carried out on both microbiological and physico-chemical aspects. A combination of techniques including the use of light microscopy (LM), confocal laser scanning microscopy (CLSM), transmission electron microscopy (SEM) and Fluorescent In Situ Hybridisation (FISH) was used to study the characteristics of microbial aggregates and to locate microbial populations within these aggregates. The microbial populations visualised using FISH techniques were Bacteria, Archaea, Methanobacteriaceae, Methanomicrobiales and Methanosarcinaceae. The performance of digesters was also monitored by measuring bulk parameters such as concentration of residual substrates, intermediate products (LCFAs, volatile fatty acids), methane (or gas) production rate and chemical oxygen demand of treated effluent.
Initially batch assays were carried out to determine the effects of glucose (hydrolysis product of carbohydrate) and cysteine (hydrolysis product of protein) on the toxicity of sodium oleate (hydrolysis product of lipid) to methanogenesis. The results showed that glucose and cysteine addition could reduce the toxicity of sodium oleate on the methanogenesis and enhance the degradation of sodium oleate. While the addition of glucose had a better effect than cysteine on decreasing the toxicity of sodium oleate, the combination of glucose and cysteine had the optimal result to stimulate the degradation of sodium oleate.
Secondly the effect of addition of glucose, cysteine and sodium oleate as co-substrates on the characteristics of granules in an LCFA fed single stage UASB were investigated. It was shown that the addition of glucose produced the best results on the formation of granules while both cysteine and sodium oleate adversely affected the granule formation. In a LCFA inhibited digester glucose and cysteine addition enhanced the recoveries of different anaerobic microbial communities. Although the effects of glucose and cysteine on the various microbial groups were different, the combination of glucose and cysteine had the optimal results on recoveries of all bacterial groups.
The next half of the thesis investigated the influence of starch and yeast extract on the hydrolysis and degradation of canola oil by application of one and two stage UASB reactors. The results showed that the combined addition of protein and carbohydrate had an optimal effect on enhancing the hydrolysis of lipid compared to the addition of only protein or carbohydrate by promoting a balanced growth of the microbial groups. It was also demonstrated that a two- stage UASB reactor performed better in terms of extent of lipid hydrolysis and methanogenesis than a one-stage UASB reactor.
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Calonne, Maryline. "Impact des hydrocarbures aromatiques polycycliques sur le métabolisme lipidique et le transport du phosphore chez le champignon mycorhizien à arbuscules Rhizophagus irregularis." Thesis, Littoral, 2012. http://www.theses.fr/2012DUNK0311/document.
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Les hydrocarbures aromatiques polycyliques (HAPs) figurent parmi les polluants organiques persistants majeurs des sols pollués et présentent une toxicité avérée vis-à-vis de l'homme et des écosystèmes. Parmi les méthodes de remédiation des sols pollués par les HAPs, la phytoremédiation assistée par les champignons mycorhiziens à arbuscules (CMA), pourrait représenter une alternative innovante, écologique et économique. L'utilisation des mycorhizes comme outil de phytoremédiation des sols pollués présente plusieurs avantages dont une meilleure tolérance à la toxicité des HAPs, une meilleure nutrition hydrique et minérale ainsi qu'une meilleure dissipation des HAPs. De rares études ont décrit l'impact des HAPs sur le développement des CMA en lien avec une péroxydation lipidique et une perturbation des teneurs en lipides du CMA, mais ni les cibles d'action de ces polluants au niveau du métabolisme lipidique, ni le rôle de ces modifications dans sa tolérance aux HAPs et dans leur dissipation n'ont été étudiés. C'est pourquoi, le premier objectif de ce travail vise tout d'abord à comprendre l'impact des HAPs sur le métabolisme lipidique. Le radiomarquage par l'acétate [1-¹⁴C] a permis de montrer une perturbation de la biosynthèse des lipides membranaires du CMA extra-racinaire. D'autre part, nos résultats montrent que les HAPs affectent la nutrition phosphatée. Par ailleurs, la capacité des mycorhizes à dégrader et à bioaccumuler le benzo[a]pyrène est démontrée. Enfin, l'implication du métabolisme des lipides de réserve (les triacylglycérols) du mycélium extra-racinaire dans la régénération des membranes altérées, la lutte contre le stress oxydant induit par les HAPs et dans leur métabolisation/bioaccumulation est discutée<br>Polycyclic aromatic hydrocarbons (PAHs) are among the major persistent organic pollutant frequently found in the polluted soils and are harmful for human health and its environment. To clean-up the PAHs polluted soils, phytoremediation assisted by arbuscular mycorrhizal fungi (AMF) could represent an innovative, ecological and cost-effective alternative. The use of mycorrhizas, as phytoremediation tool, has several advantages including increased tolerance to the pollutant toxicity, improved water and mineral nutrition as well as a better pollutant dissipation. Few studies have described the impact of PAHs on the AMF development related with lipid peroxidation and total lipid content disturbance. However, so far neither the target action of these pollutants on the metabolism, nor the role of these lipid changes in PAH tolerance and in their dissipation have been studied. Therefore, the present work aims firstly to improve our understanding of the PAHs impact on the CMA lipid metabolism. Thanks to radiolabeling experiments with [1-¹⁴C] acetate, our results showed a disruption of the membrane lipid biosynthesis pathways in the AMF extraradical mycelium, grown in the presence of PAHs. Secondly, it was highlighted that the PAHs affectef the phosphate nutrition. Finally, the mycorrhizas abilities to degrade and to bioaccumulate the benzo[a]pyrene, were pointed out. The involvement of extraradical mycelium storage lipid (triacyglycerols) metabolism in the membrane regeneration, the fight against the PAH induced-oxidative stress and the PAH metabolism/bioaccumulation is discussed
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Bröder, Lisa-Marie. "Transport, degradation and burial of organic matter released from permafrost to the East Siberian Arctic Shelf." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-136380.
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Permafrost soils in the Arctic store large quantities of organic matter, roughly twice the amount of carbon that was present in the atmosphere before the industrial revolution. This freeze-locked carbon pool is susceptible to thawing caused by amplified global warming at high latitudes. The remobilization of old permafrost carbon facilitates its degradation to carbon dioxide and methane, thereby providing a positive feedback to climate change. Accelerating coastal erosion in addition to projected rising river discharge with enhancing sediment loads are anticipated to transport increasing amounts of land-derived organic carbon (OC) to the Arctic Ocean. On its shallow continental shelves, this material may be remineralized in the water column or in the sediments, transported without being altered off shelf towards the deep sea of the Arctic Interior or buried in marine sediments and hence sequestered from the contemporary carbon cycle. The fate of terrigenous material in the marine environment, though offering potentially important mechanisms to either strengthen or attenuate the permafrost-carbon climate feedback, is so far insufficiently understood. In this doctoral thesis, sediments from the wide East Siberian Arctic Shelf, the world’s largest shelf-sea system, were used to investigate some of the key processes for OC cycling. A range of bulk sediment properties, carbon isotopes and molecular markers were employed to elucidate the relative importance of different organic matter sources, the role of cross-shelf transport and the relevance of degradation during transport and after burial. Overall, OC released from thawing permafrost constitutes a significant proportion of the sedimentary organic matter on the East Siberian Arctic Shelf. Two sediment cores from the inner and outer East Siberian Sea recorded no substantial changes in source material or clear trends in degradation status for the last century. With increasing distance from the coast, however, strong gradients were detected towards lower concentrations of increasingly reworked land-derived OC. The time spent during cross-shelf transport was consequently found to exert first-order control on degradation. Compound-specific radiocarbon dating on terrigenous biomarkers revealed a net transport time of ~4 000 years across the 600 km wide Laptev Sea shelf, yielding degradation rate constants for bulk terrigenous OC and specific biomarkers on the order of 2-4 kyr-1. From these results, the carbon flux released by degradation of terrigenous OC in surface sediments was estimated to be ~1.7 Gg yr-1, several orders of magnitude lower than what had been quantified earlier for dissolved and particulate OC in the water column. Lower oxygen availability and close associations with the mineral matrix may protect sedimentary OC from remineralization and thereby weaken the permafrost-carbon feedback to present climate change.<br><p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Submitted. Paper 4: Manuscript.</p>
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Santos, Carla Cristina (Lucas Kyem) Araújo dos. "Tratamento de efluente de laticínio em reator anaeróbio compartimentado." Universidade de São Paulo, 2016. http://www.teses.usp.br/teses/disponiveis/74/74132/tde-23082016-093549/.
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Os efluentes com elevadas concentrações de lipídios, apesar de demonstrarem elevado potencial para produção de metano podem causar inibição da atividade do consórcio anaeróbio, impossibilitando a produção de biogás. O presente trabalho teve como objetivo o estudo de um reator anaeróbio compartimentado (ABR) com cinco compartimentos tratando efluente simulado de laticínio. Para tanto, a biomassa, foi adaptada por 51 dias e em seguida submetida a tempos de detenção de hidráulica (TDH) de 72h, 24h e 12h, tendo o monitoramento se estendido por 340 dias. Enquanto operando com TDH de 24, o sistema foi submetido a choques hidráulicos e de carga orgânica através da diminuição do TDH para 12 h. O reator absorveu bem a carga, e em 36 horas recuperou os valores prévios de eficiência. Quando operou permanentemente com 12 horas, todavia, problemas de flotação de biomassa e obstruções foram constantes. As eficiências de remoção de matéria orgânica alcançadas para cada condição aplicada foram de 92 ± 3,0; 91 ± 1,8 e 90 ± 2,4% para os TDH de 72h, 24h e 12h, respectivamente. Esses valores foram estatisticamente semelhantes (Anova e L-Fisher). A percentagem de metano no biogás aumentou com a redução de TDH, tendo sido 41 ± 23, 53 ± 27 e 62 ± 12% quando os TDH foram 72, 24 e 12 horas, respectivamente. A produção média de alcalinidade foi de 320±25 mg.CaCO3.L-1, sendo esta observada desde o início da operação. A relação média entre alcalinidade intermediária e parcial foi de 0.1±0.06 em amostras coletadas na saída do sistema. Embora apresentando problemas de obstrução com o menor TDH, o ABR foi eficiente, robusto e confiável ao tratar efluente de laticínios, tendo produzido um efluente líquido de alta qualidade e biogás rico em metano.<br>Effluents with high concentrations of lipids, although demonstrating high potential for methane production represents potential inhibition of the anaerobic consortium activity, depleting the production of biogas. This project was carried out monitoring an anaerobic hybrid baffled reactor with five compartments (ABR) treating simulated dairy wastewater. The biomass, was adapted for 51 days and then subjected to hydraulic retention times (HDT) of 72h, 24h and 12h, resulting in a monitoring period of 340 days. While operating with 24h of HRT, the system was subjected to three organic and hydraulic shock loads, when its HDT was decreased to 12 h. The reactor absorbed the shock within 36 hours, achieving similar efficiencies to the previous condition. Nevertheless, although presenting high organic matter efficiencies, when permanently operating with HDT of 12 h, clogging problems due to biomass flotation were constant. The organic matter removal efficiencies for each operational condition were 92 ± 3%, 91 ± 1.8%, 90 ± 2,4%. Those values were statistically similar. The methane percentage in the biogas increased with the HDT reduction, being 41 ± 23, 53 ± 27, and 62 ± 12% when the HDT were 72, 24 and 12 hours. Alkalinity production was observed since the beginning of operation. The mean relation between intermediate and partial alkalinity was 0.1±0.006 in samples collected in the system output. Although presenting clogging problems with the smallest HDT, the ABR was efficient, robust and reliable when treating dairy effluents, producing a high quality liquid effluent and a methane rich biogas.
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Karlsson, Emma. "Compositional clues to sources and sinks of terrestrial organic matter transported to the Eurasian Arctic shelf." Doctoral thesis, Stockholms universitet, Institutionen för miljövetenskap och analytisk kemi, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-116876.
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The amount of organic carbon (OC) present in Siberian Arctic permafrost soils is estimated at twice the amount of carbon currently in the atmosphere. The shelf seas of the Arctic Ocean receive large amounts of this terrestrial OC from Eurasian Arctic rivers and from coastal erosion. Degradation of this land-derived material in the sea would result in the production of dissolved carbon dioxide and may then add to the atmospheric carbon dioxide reservoir. Observations from the Siberian Arctic suggest that transfer of carbon from land to the marine environment is accelerating. However, it is not clear how much of the transported OC is degraded and oxidized, nor how much is removed from the active carbon cycle by burial in marine sediment. Using bulk geochemical parameters, total OC, d13C and D14C isotope composition, and specific molecular markers of plant wax lipids and lignin phenols, the abundance and composition of OC was determined in both dissolved and particulate carrier phases: the colloidal OC (COC; part of the dissolved OC), particulate OC (POC), and sedimentary OC (SOC). Statistical modelling was used to quantify the relative contribution of OC sources to these phases. Terrestrial OC is derived from the seasonally thawing top layer of permafrost soil (topsoil OC) and frozen OC derived from beneath the active layer eroded at the coast, commonly identified as yedoma ice complex deposit OC (yedoma ICD-OC). These carbon pools are transported differently in the aquatic conduits. Topsoil OC was found in young DOC and POC, in the river water, and the shelf water column, suggesting long-distance transport of this fraction. The yedoma ICD-OC was found as old particulate OC that settles out rapidly to the underlying sediment and is laterally transported across the shelf, likely dispersed by bottom nepheloid layer transport or via ice rafting. These two modes of OC transport resulted in different degradation states of topsoil OC and yedoma ICD-OC. Terrestrial CuO oxidation derived biomarkers indicated a highly degraded component in the COC. In contrast, the terrestrial component of the SOC was much less degraded. In line with earlier suggestions the mineral component in yedoma ICD functions as weight and surface protection of the associated OC, which led to burial in the sediment, and limited OC degradation. The degradability of the terrestrial OC in shelf sediment was also addressed in direct incubation studies. Molecular markers indicate marine OC (from primary production) was more readily degraded than terrestrial OC. Degradation was also faster in sediment from the East Siberian Sea, where the marine contribution was higher compared to the Laptev Sea. Although terrestrial carbon in the sediment was degraded slower, the terrestrial component also contributed to carbon dioxide formation in the incubations of marine sediment. These results contribute to our understanding of the marine fate of land-derived OC from the Siberian Arctic. The mobilization of topsoil OC is expected to grow in magnitude with climate warming and associated active layer deepening. This translocated topsoil OC component was found to be highly degraded, which suggests degradation during transport and a possible contribution to atmospheric carbon dioxide. Similarly, the yedoma ICD-OC (and or old mineral soil carbon) may become a stronger source with accelerated warming, but slow degradation may limit its impact on active carbon cycling in the Siberian Shelf Seas.<br><p>At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript.</p>
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Kuo, Shu-Jung. "Chilling-induced lipid degradation in cucumber fruit (Cucumis sativa L.)." 1989. http://catalog.hathitrust.org/api/volumes/oclc/20051854.html.
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Thesis (M.S.)--University of Wisconsin--Madison, 1989.<br>Typescript. eContent provider-neutral record in process. Description based on print version record. Includes bibliographical references (leaves 112-133).
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Thiam, Tan Kien, та 陳健添. "β-Adrenergic Receptor-Stimulated Lipolysis Required the Rab7-Mediated Autolysosomal Lipid Degradation". Thesis, 2011. http://ndltd.ncl.edu.tw/handle/4tdf2u.
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博士<br>國防醫學院<br>生命科學研究所<br>99<br>The hormone-stimulated lipolysis is a rapid way to mobilize fat from its storage depot for use in peripheral tissues. The only molecular mechanism considered so far is the activation of cellular lipases by β-adrenergic receptor (β-AR)/cAMP signal pathway to liberate fatty acids from triglycerides that are stored in lipid droplets (LDs) of cells. This study provides evidence showing that autophagy activity contributes in significant part to this stimulated lipolysis. The pharmacological inhibitors and the shRNA-based gene inhibition on the early or late autophagy reduce significantly the stimulated lipolysis. Upon β-AR activation, there is a marked increase in the autophagy-targeted LDs for lysosomal degradation, which is dependent on the LD-associated Rab7. Rab7 is physically interacts with perilipin, and this interaction is significantly enhanced by the β-activation. The dominant negative mutant of Rab7 not only abolishes its association with LDs but also eliminate the recruitment of autophagic components to LDs during the β-AR activation.
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Ding, Haibing. "Study of biogeochemical factors affecting organic matter (lipid biomarkers) degradation structural association, redox condition, enzymatic response, and benthic macrofaunal activity /." 2004. http://purl.galileo.usg.edu/uga%5Fetd/ding%5Fhaibing%5F200412%5Fphd.
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Thesis (Ph. D.)--University of Georgia, 2004.<br>Directed by Ming-Yi Sun. Includes articles submitted to Geochimica et cosmochimica acta, and Limnology and oceanography, and an article accepted by Marine chemistry. Includes bibliographical references.
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Mißbach, Helge. "Formation and preservation of abiotic organic signatures vs. lipid biomarkers—experimental studies in preparation for the ExoMars 2020 mission." Thesis, 2018. http://hdl.handle.net/11858/00-1735-0000-002E-E42A-7.
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Rudolph, Maike. "Mobilisierung von Speicherlipiden in Cucumis sativus- und Arabodopsis thaliana-Keimlingen." Doctoral thesis, 2008. http://hdl.handle.net/11858/00-1735-0000-0006-B653-9.
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WU, Jong-Che, and 吳榮哲. "Anaerobic Biotechnology for Domestic Wastewater Treatment—Explore the Degradation of Sugars, Proteins and Lipids." Thesis, 2019. http://ndltd.ncl.edu.tw/handle/pa2am3.
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碩士<br>國立臺灣大學<br>環境工程學研究所<br>107<br>This research, the fixed anaerobic biological treatment module was used to test the continuous influent of the whole domestic wastewater. The operating temperature was set to 25 °C, and the results were analyzed in four phases of hydraulic retention time (HRT) at 16, 12, 8 and 6 hours.
The results showed that the total average removal rate of chemical oxygen demand (TCOD) was 76.5% and for the average removal rate of each phase, the average removal rate at HRT of 16 hours was 75.5%, 76.3% at HRT of 12 hours, 78.7% at HRT of 8 hours and 74.6% at HRT of 6 hours.
At HRT of 6 hours and the operating condition of sudden load increase, the average TCOD of effluent was 62 mg/L (maximum 77 mg/L and minimum 49 mg/L), which was consistent with the emission standards for chemical oxygen demand of the discharged water (COD, 100mg/L), showing the stability of the fixed anaerobic biological treatment system for sudden load increase and low hydraulic retention time (HRT) that satisfied the current demand of domestic wastewater treatment via the fixed anaerobic biological treatment system. Such system does not require continuous aeration and the production of waste sludge is extremely low, which conserves electricity and tremendously reduces the sludge disposal cost.
The analytic results of major organic components in three types of domestic wastewater, such as sugars, proteins and lipids, showed that the reduction rate of sugars and proteins could achieve more than 80% under the operating condition of any hydraulic retention time, where the level of lipids could only be maintained between 40% and 60%. It was obvious that the removal efficiency of lipids was the limiting factor for the fixed anaerobic biological treatment system. The improvement to degradation efficiency of lipids in the co-degradation effect of sugars, proteins and lipids is the key issue to enhance the overall effectiveness of the fixed anaerobic biological treatment system.
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Ramôa, Renata Filipa Esteves. "Use of yeasts as bioremediation agents: application to hydrocarbons and phenolic compounds degradation." Master's thesis, 2018. http://hdl.handle.net/1822/59255.
Full textAbstract:
Dissertação de mestrado em Biotechnology<br>Liquid effluents of petrochemical industry and olive oil processing (olive mill wastewater, OMW) are two examples of effluents contaminated with pollutant compounds, respectively hydrocarbons and phenolic compounds. Biodegradation strategies involving microorganisms to simultaneously degrade these pollutants and obtain high added-value products have become an interesting and environment friendly approach.
This work address the study of the ability of ten yeast species to grow on hydrocarbons (hexadecane) and phenolic compounds (tyrosol, phenol and catechol) as sole carbon and energy source. After a preliminary screening in Petri plates and 96-well microplate, two yeast species demonstrated an extraordinary ability to grow on hexadecane 1 g·L-1 (Yarrowia lipolytica W29) and phenolic compounds 1 g·L-1 (Candida tropicalis ATCC 250).
In Erlenmeyer flask experiments, it was observed that Y. lipolytica W29 was able to grow on hexadecane 10 g·L-1, hexadecene 7.5 g·L-1 and in a mixture with both hydrocarbons (5 g·L-1 of each one).
The increase of oxygen transfer, by raising the ratio of the volumes of headspace and liquid medium in flasks, had a positive effect on cellular growth and metabolites production. In hexadecane-based medium, for example, yeast cells produced lipase (up to 1260 U·L-1) and accumulated microbial lipids (up to 15 %, w/w), demonstrating its ability to valorize effluents contaminated with hydrocarbons. As C. tropicalis shown high potential to grow in phenolic compounds, its ability to grow on undiluted OMW (supplemented and non-supplemented with YNB) and produce added-value compounds was tested in Erlenmeyer flasks. The increase of flask headspace clearly enhanced the cellular growth, but did not favor the intracellular lipids accumulation. By contrast, it was observed that nitrogen limitation led to an enhancement of microbial lipids content: 39 % (w/w) and 24 % (w/w) of lipids were accumulated, respectively, in non-supplemented OMW medium and in repeated batch culture (pulses of OMW without YNB).
Microbial lipids accumulated both by Y. lipolytica and C. tropicalis were mainly composed by oleic and linoleic acids and the unsaturated fraction exceeded the saturated one. The composition of these lipids, similar to that of common vegetable oils, makes them a potential feedstock for biodiesel production.<br>Os efluentes líquidos da indústria petroquímica e do processamento do azeite (águas ruças) são dois exemplos de efluentes contaminados com compostos poluentes, respetivamente hidrocarbonetos e compostos fenólicos. A biodegradação destes por microrganismos, obtendo simultaneamente compostos de alto valor acrescentado, tem-se tornado uma abordagem interessante e amiga do ambiente.
Este trabalho aborda o estudo da capacidade de 10 espécies de leveduras para crescerem em hidrocarbonetos (hexadecano) e compostos fenólicos (tirosol, fenol e catecol) como única fonte de carbono e energia. Os ensaios preliminares em placa de Petri e microplaca demonstraram que Yarrowia lipolytica W29 crescia bem em 1 g·L-1 de hexadecano e Candida tropicalis ATCC 250 era capaz de crescer em 1 g·L-1 de cada composto fenólico.
Nos ensaios realizados em frascos Erlenmeyer, Y. lipolytica W29 conseguiu crescer na presença de 10 g·L-1 de hexadecano, 7.5 g·L-1 de hexadeceno e numa mistura dos dois (5 g·L-1 de cada hidrocarboneto). O aumento da transferência de oxigénio, por aumento da razão do volume de headspace e do meio líquido dos frascos, teve um efeito positivo no crescimento e na produção de metabolitos. No meio com hexadecano, as células produziram lipase (1260 U·L-1) e acumularam lípidos intracelularmente (15 %, p/p), demonstrando o seu potencial para valorizar efluentes contaminados com hidrocarbonetos. Como a levedura C. tropicalis demonstrou potencial para crescer em compostos fenólicos, foi testada em frascos Erlenmeyer a sua capacidade para crescer em águas ruças não diluídas (com e sem suplementação com YNB) e produzir metabolitos de interesse. O aumento do volume do frasco levou ao aumento do crescimento celular, mas não favoreceu a acumulação de lípidos. Foi também observado que a limitação de azoto favorecia a acumulação de lípidos: no meio não suplementado com YNB obteve-se um conteúdo de lípidos igual a 39 % (p/p) e nos ensaios realizados em culturas descontínuas repetidas (pulsos de águas ruças sem YNB) obteve-se 24 % (p/p) de lípidos microbianos.
Os lípidos microbianos acumulados por Y. lipolytica e C. tropicalis eram compostos maioritariamente por ácidos oleico e linoleico, e a fração insaturada era maior que a saturada. A composição destes lípidos microbianos, semelhante à dos óleos vegetais comuns, torna-os uma potencial matéria-prima para a produção de biodiesel.